US1895930A

US1895930A - Shaft packing

Info

Publication number: US1895930A
Application number: US559756A
Authority: US
Inventors: Junggren Oscar
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1931-08-27
Filing date: 1931-08-27
Publication date: 1933-01-31
Anticipated expiration: 1950-01-31

Description

Jan. 31, 1933. o; JUNGGREN 1,895,930

SHAFT PACKING Filed Aug. 27, 1931 Inv entor Oscar Jung gfen,

His Attorneg Patented Jan. 31, 1933 UNITED STATES PATENT? rricefj P oscan JUNGGREN, or sorrnnnoreny, new YORK, ASSEGNOR' T (name. ELECTRIC COMPANY, 1 conronarronor new YORK v Y SHAFT PACKING Application filed August 27,.1931. Serial No. 559,756.

The present invention refers to shaft packings, particularly to packings of the type disclosed in my Patent No. 1,67 0,071.

Difficulties have been encountered in prop-' erly providing packings for elastic fluid turbines operating with high temperature and high pressure elastic fluid of the orders of 1200 lbs. for example. Specifically t has been found that owing to unequal ratiosof expansion of different parts, the inner packing member which heretofore has been shrunk on to the shaft becomes loose and permits leakage of elastic fluid along the shaft. It will be readily understood that the loosening occurs particularly during the starting of the turbine as the inner packing member which is in direct contact withthe high temperature fluid heats up more rapidly than the shaft. Although the clearance between the shaft and the inner packing member which is due to this unequal expansion is small it will permit under the high pressure conditions in modern turbines a substantial loss of fluid. V

The object of my invention accordingly is an improved arrangement, primarily of the inner packing member of elastic fluid turbines, although it is not necessarily limited thereto.

For a consideration of what'I believe to be novel and my invention, attention is directed to the following description and the claims in connection with the drawing appended hereto. 1

In the drawing Iliave shown, by way of example, a sectional view of a packing applied to an elastic fluidturbine embodying my invention.

Referring to the drawing, 1 designates a rotary turbine shaft, 2 is a bucket wheel fastened to the shaft and 3 indicates the turbine casing through which the shaft passes and between which and the shaftit is desired to prevent leakage. The packing comprises inner rotary and outer stationary packing members 4 and 5 carried by the shaft and the casing respectively and provided with cooperating packing teeth which in the one instance are straight and have very thin packing edges and in the other instance are sloping and have flat, axially extended surfacesfagainst which, the teeth with the thin edges pack.

The sloping teeth'point ina direction [0P1 posite'to the direction of flow of leakage fluid. Whereas I have shown onlythe upper part of the structure it should be understood that these elements are cylindricallylfo'rmed and are concentrically. arranged with respect to the turbine shaft. 'The structure i g so far described may be taken as'typical for any packing surrounding-a rotary shaft.

In order to prevent loosening of the inner packing member 6 which is in direct contact with the high pressure, high temperature elastic fluid and therefore expands morerap: idly than the shaft, I provide according to my invention means for locking the inner packing member 6 to the shaft whereby .a

substantial relative expansion between these parts is eliminated. ,This means has been shown in the'present instance as comprisin an annular, axially extending pro ec t1on integrally formed with one, end of packing lnember 6 and engaging the-undercut hub of wheel disk 2. The other end of member 6 is shown as being integrally formed-with a flanged portion 9 which isundercut at 10 and engages the under side of an annular shoulder 11 of the shaft. In assembling, the

packing member 6 is slid over the shaft until members 7 and 9 engage the under sides of parts 8 and 11 respectively. In'order to prevent axial movement of ring'G I provide a' I spring ring 12 engaging an annulargroove l of the shaft. Ring 12 is held in its position by another spring ring 13 engaging the out er surface of ring 12 and a shoulder of member6; Ring 13 is maintained in its position by. peening over the edge of ring 6 as indicated at 14. r I

From anotherviewpointthe rotary shaft 1 and wheel disk 2 represent a machine part provided with shoulders 8 and 11 having recesses at different horizontal planes. One

end, 7, of member 6 defines a projection which is located within the recess of shoulder 8, whereas the recess provided in shoulder 11 receives a recessed flanged portion 9 at the other end of member 6; v

From a consideration of the drawing in Q. gaging the undercuthub of the disk.

7 connection with the above description it will be; readily understood that the means for securing the inner packing member to the i I shaft are readily-l adapted to prevent substantial relative movement between' this member and the shaft to the effect that no leakage between thering and the shaft can occur. It will also be seen that the joints which are formed between members 7 and 8, and 9 and 11respectively are tightened dur- I ing the starting operation owing'to the fact that member6 :is in direct contact with the i high temperature elastic fluid and therefore heats up more rapidly than the shaft. The

engagement between the; inner packing mem-' ber and the shaft is therefore tightened'during starting which is just theoppo'site'efiect to that'obtained with; arrangements 7 hereto- 0. fore used. '2

" Having tionmay be carriedout by other means, 7

yWhat I claim'as new and desire to secure by Letters Patent. of the United States is:

1 1. Incombination, a rotating shaft having an undercut shoulder, a wheel disk having an undercut hubfastened to the shaft, a pack ing surrounding-the shaft and including an inner packing'member carriedby the shaft, 7 and means for preventing substantial'rela-V tive radial expansion between the inner member and the shaft, said meanscomprising an E undercut flanged portion integrally formed with one end of the inner member and engaging the underside of said shoulder, and an annular projection integrally formed with the other end of the inner member and em I 2. In combination, a machine part having two shouldersspaced apart and provided -with recesses in different planes, a member,

and means for locking the-member ,to said machine part to prevent during heating relav tive expansion therebetween, said imeans -comprising a projection provided atone end hand. 7

of the member and located within one ofthe jrecesses, a recessed flanged portion at the other end of the memberfor receiving the other recessed shoulder of the machine part, and a key for holding the member in interlocked relation with'the machine part.

' In witnesswhereof I have hereunto set my osonn JUNGGBEN.

I described my invention, together with the apparatus whichl now considerto represent the best embodiment thereof, Ide "sire 'to'have it understood that the apparatus shown is only'illustrative andthat theinven-